The present invention relates to a serial printer comprising a platen rotatably mounted on a base, a carriage for supporting a printing device slidable on guides parallel to the platen, and a frame pivoted on the base of the machine and on which the guides are mounted.
A known serial printer comprises a printing unit carried by a carriage which slides transversely, along the length of the platen on a pair of guides, by means of a motor and a flexible cable for connection between the motor and the carriage. The guides on which the carriage slides are carried by a frame pivoted in a projecting manner on two lateral tongues of one end, on a relatively short fixed shaft which lies in a plane orthogonal to the platen. In the working position the frame is coupled to a side of the base and the guides lie parallel to the platen. By manually rotating it with respect to the shaft on which it is pivoted, the frame can be spaced from the other end of the platen in such a way that the user can gain access to the rear part of the printing device and the carriage for maintenance. This printer has the disadvantage of occupying considerable space when the frame is open and of not being suitable for accepting a keyboard or a control console in front of it. Moreover, the projection of the frame with respect to the base, and the weight of the motor, the carriage and the frame itself requires a very heavy structure the weight of which is borne on the pin and makes it subject to significant wear. A second disadvantage lies in the fact that the connection cable between the carriage and the motor and the various pulleys are subjected to wear which varies the geometric conditions between the parts so that the tension of the cable requires periodic adjustment.